OCV is only held in with a 10mm bolt so should come out nice and easy when the bolt is out. There is a rubber o ring seal too - very strange it broke (got a pic of it?)

Mart.

hello mart i will put the pic, first thing in the morning , i opened the 10mm bolt but when i pulled it only end part came out and the rest is inside it is a little valve in it and a small spring on the end of it ! thanks for ur reply